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41.
The safety and potential efficacy of FK506 in combination with a short course of methotrexate (MTX) for the prevention of acute graft-versus- host disease (GVHD) after marrow transplantation from HLA-matched unrelated donors was evaluated in a single-arm Phase II study conducted at two centers. Forty-three patients, 15 to 54 (median 41) years of age, were transplanted for hematologic malignancies. Thirty-seven of 43 evaluable patients had evidence of sustained marrow engraftment. Five patients died before day 17 after transplantation. The median time to an absolute neutrophil count of > 0.5 x 10(5)/L was 21 (range, 14 to 30) days. Nephrotoxicity (serum creatinine concentration > 2 mg/dL or doubling of baseline) occurred in 32 patients (74% cumulative incidence during the first 100 days after transplant). Other adverse effects included hypertension (n = 27), hyperglycemia (n = 27), neurotoxicity (n = 9) and thrombotic thrombocytopenic purpura (n = 2). Severe veno- occlusive disease of the liver occurred in 9 (21%) of the 43 patients. Eighteen patients (42%) developed grades II to IV acute GVHD and five (12%) developed grades III to IV acute GVHD. Twelve of 25 evaluable patients developed extensive chronic GVHD within 1 year of marrow transplantation resulting in an estimate of the probability of developing this complication of 48%. The cumulative incidence of transplant-related mortality during the first 100 days was 37%. Kaplan- Meier estimates of disease-free survival at 2 years for good-risk, poor- risk, and all patients were 65%, 4%, and 32%, respectively. FK506 in combination with a short course of MTX appears active in preventing acute GVHD after marrow transplantation from unrelated donors. Further studies comparing the combination of FK506 and MTX with cyclosporine and MTX for the prevention of acute GVHD are warranted.  相似文献   
42.
The 14q+ chromosome in pre-B-ALL   总被引:2,自引:0,他引:2  
Kaneko  Y; Rowley  JD; Check  I; Variakojis  D; Moohr  JW 《Blood》1980,56(5):782-785
A child who had acute lymphoblastic leukemia (ALL) associated with an 8;14 chromosome translocation and with a pre-B phenotype is described. The leukemic cells were determined to be pre-B-cells on the basis of intracytoplasmic mu-chain immunoglobulin (cIgM+) and the common-ALL antigen, lack of receptors for sheep erythrocytes, and lack of surface immunoglobulin. The 8;14 translocation is frequently found in patients with Burkitt's lymphoma and in most patients with B-cell ALL and is known to carry a poor prognosis. Thus far, no karyotypes have been reported for patients with pre-B-ALL. The present case indicates that a 14q+ chromosome may provide a proliferative advantage not only to cells with a B-cell phenotype, but also to pre-B-cells. The short survival of our patient also suggests that the 14q+ abnormality and the pre-B phenotype may signal a poor prognosis.  相似文献   
43.
Samples from prospectively followed recipients, their respective donors, and a cohort of random donors were used to evaluate the specificity and efficacy of a recombinant immunoblot assay (RIBA) as an adjunct to anti-hepatitis C virus (HCV) testing by enzyme immunoassay (EIA). RIBA reacted (RIBA+) in 100 percent of patients who developed hepatitis associated with anti-HCV seroconversion documented by EIA and in 100 percent of the EIA-positive (EIA+) donors implicated in these cases. In contrast, RIBA reacted in none of 10 recipients who were EIA+ but did not develop hepatitis, in none of 7 EIA+ patients with hepatitis B or cytomegalovirus infection, in 33 percent of EIA+ donors who were not implicated in hepatitis transmission, and in 37 percent of EIA+ random donors. Hence, the vast majority of EIA+ individuals who have ancillary evidence of HCV infection react on RIBA, whereas the majority of EIA+ individuals in low-risk settings do not react (RIBA-negative, or RIBA-). There was a strong association between RIBA reactivity and the presence of a surrogate marker (elevated alanine aminotransferase [ALT] and/or antibody to hepatitis B core antigen); 43 percent of RIBA+ implicated donors had a surrogate marker as compared to none of 14 EIA+, RIBA- donors. Among EIA+ random donors, 77 percent of those with a surrogate marker were RIBA+, as compared with 29 percent of those without a surrogate marker. In addition, in EIA+ donors, RIBA reactivity correlated with the extent of ALT elevation; 86 percent of those with an ALT greater than 135 IU per L were RIBA+ compared with 18 percent of those with an ALT less than 30 IU per L.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
44.
Dessypris  EN; Redline  S; Harris  JW; Krantz  SB 《Blood》1985,65(4):789-794
The pathogenesis of diphenylhydantoin-induced pure red cell aplasia was investigated in the case of a 32-year-old man who developed pure red cell aplasia while he was under treatment with diphenylhydantoin. The patient's serum IgG purified from serum drawn at the time of diagnosis suppressed normal allogeneic marrow colony-forming (CFU-E) and burst- forming (BFU-E) and autologous blood BFU-E growth in vitro only in the presence of diphenylhydantoin. This IgG-diphenylhydantoin complex had no effect on CFU-GM growth in vitro. Normal IgG or patient's IgG purified from serum drawn after the remission of red cell aplasia had no effect on erythroid colony formation in vitro in the presence of diphenylhydantoin. The IgG-diphenylhydantoin complex exerted no direct cytotoxic effect on normal marrow erythroblasts, CFU-E, and BFU-E, nor did it interfere with the action of erythropoietin on marrow erythroblasts. These studies suggest that diphenylhydantoin-induced red cell aplasia is immunologically mediated through an IgG inhibitor, which requires the presence of the drug to suppress erythroid colony formation in vitro. This inhibitor seems to exert its effect on erythroid progenitors at or beyond the stage of differentiation of CFU- E, but not on erythroblasts.  相似文献   
45.
目的:分析壳聚糖-DNA超微颗粒在关节内的转基因效应。方法:实验于2005-09/2006-06在上海交通大学医学院健康科学研究所骨科细胞与分子生物学实验室完成。实验材料:①模型制备:采用切断内侧副韧带,切除内侧半月板的方法制备骨关节炎兔模型。②基因产品:白细胞介素(interleukin,IL)1Ra基因、IL-10基因。实验分组:15只新西兰兔按随机数字表法分为3组:①空载体对照组(n=3),造模后5d两侧膝关节关节腔注射400μL壳聚糖-PcDNA3.1溶液,共3次,每48h1次。②IL-1Ra基因治疗组和IL-10基因治疗组,每组6只,造模后5d对照侧膝关节关节腔分别注射20μg裸DNA(PcDNA3.1-IL-1Ra或PcDNA3.1-IL-10),实验侧膝关节关节腔注射400μL壳聚糖-DNA超微颗粒(含20μgIL-1Ra或IL-10),注射次数及间隔时间同空载体对照组。实验评估:①采用酶联免疫吸附分析及免疫组织化学检测IL-1Ra和IL-10基因的表达和分布。②苏木精-伊红染色和甲苯胺蓝染色观察骨关节炎软骨组织学变化。结果:纳入新西兰兔15只,均进入结果分析。①IL-1Ra和IL-10基因在关节滑液中的表达:空载体对照组及IL-1Ra基因治疗组对照侧膝关节滑液中未检测到IL-1Ra表达,实验侧于第1次基因注射后7,14d检测到IL-1Ra表达。IL-10基因治疗组对照侧和实验侧均未检测到IL-10表达。②IL-1Ra基因在兔膝关节的分布:IL-1Ra基因治疗组兔软骨表层和中间层部分细胞内表达IL-1Ra,至少持续到第1次基因注射后14d。在滑膜组织中未观察到明显的IL-1Ra表达。③兔骨关节炎软骨组织学变化:空载体对照组呈早期骨性关节炎的典型性改变。苏木精-伊红染色显示软骨细胞坏死,蛋白多糖甲苯胺蓝染色不均一,软骨表层和中间层大部分区域失染,软骨细胞簇聚区域其周围深染。IL-1Ra基因治疗组在软骨损坏方面明显减轻,甲苯胺蓝部分失染。结论:①壳聚糖-DNA超微颗粒的转染效率与基因产品有关。②将IL-1Ra用关节腔直接注射壳聚糖-DNA超微颗粒的方法直接转移入关节腔能一定程度上减轻骨性关节炎的进程。  相似文献   
46.
目的:在前期微囊化基因工程细胞制备平台的基础上,构建分泌型人肿瘤坏死因子α的真核表达载体PSNAV2.0-TNFα重组质粒,并鉴定其蛋白的体外瞬时表达,为进一步利用该基因进行微囊化细胞移植治疗和改善疾病奠定基础。方法:实验于2006-06/2007-05在解放军总医院老年医学研究所细胞生物学实验室完成。①以含有人肿瘤坏死因子αcDNA序列的质粒为模板,通过PCR扩增获得人肿瘤坏死因子α基因片段;将其定向插入真核表达载体PSNAV2.0中,获得重组质粒PSNAV2.0-TNFα。采用SalⅠ和EcoRⅠ双酶切法、PCR法及插入片段序列测定法鉴定该质粒。②利用阳离子脂质体介导法,将其转染到人胚胎肾细胞HEK-293细胞中,构建可持续分泌人肿瘤坏死因子α的基因工程细胞,采用RT-PCR法和Western blot法检测转染细胞培养上清液中人肿瘤坏死因子蛋白的体外瞬时表达。结果:①通过SalⅠ和EcoRⅠ双酶切、PCR及测序鉴定证明:在HEK-293中插入片段正确。②采用RT-PCR和Western blot法检测表明HEK-293细胞培养上清中有人肿瘤坏死因子α蛋白,Mr17000。结论:成功构建了重组质粒PSNAV2.0-TNFα真核表达载体,转染HEK-293细胞后可有效分泌人肿瘤坏死因子α蛋白,并能分泌到细胞外。  相似文献   
47.
肠息肉发生的细胞和分子生物学研究进展   总被引:1,自引:0,他引:1  
肠息肉是一类从黏膜表面突出到肠腔内的隆起状病变的临床诊断.在最近的研究中陆续证实,其发生和发展的原因和机制,是由于Bmprla,APC,SMAD4,PTEN,STK11等基强突变而使各种细胞信号分子通过影响BMP信号通路,PTEN信号通路及Wnt信号通路所组成的生长信号调控网络,造成β-catenin在肠干细胞中的过度积聚,使得肠干细胞功能紊乱,导致其自我更新、克隆增殖、分化和凋亡失去平衡的结果.  相似文献   
48.
The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
49.
The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software‐predicted set‐up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set‐up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in‐plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in‐plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2–3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set‐up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set‐up error was greater than 5 mm in the anterior–posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2° to 20° for the patients. The differences between set‐up shifts determined by the online software without in‐plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set‐up for one of the patients. A larger study is required to determine the magnitude of this problem for the patient population. The inability in the current software to incorporate in‐plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate.  相似文献   
50.
Objective: To assess the accuracy and reproducibility of long-term implanted ultrasound transit-time flow probes for measuring cardiac output. Design: Prospective animal study. Settings: Animal research laboratory in a university department. Animals: Eleven anaesthetised dogs, 24–34 kg. Measurements and results: Flow probes (16–24 mm S-series, Transonic) were implanted around the pulmonary artery for a mean duration of 22 months (range 6–47 months). Comparisons (n = 147) were made between cardiac output thus obtained and that measured by the direct Fick principle using oxygen uptake (Deltatrac II Metabolic Monitor) and the arterial to mixed venous oxygen content difference measured by a galvanic cell (Lex-O2-Con-TL). Measurements were made either during baseline conditions or during pharmacologically altered cardiac output (range 22–180 ml · kg–1· min–1). Regardless of the intervention, the two methods yielded the same results in half of the dogs. In the others, however, cardiac output was underestimated by the flow probes by up to 38 % (probably because of non-perpendicular position of the probe towards the vessel). This difference was constant for the whole range of cardiac output studied and remained constant over the entire observation period for each individual dog, so that a correction factor was used. Thereafter, the mean difference between the two methods was –1.1 ml · kg–1· min–1 with a precision (SD) of 14.2 ml · kg–1· min–1 for all experiments. Conclusions: After in vivo calibration, ultrasound transit-time flow probes measure cardiac output precisely for several years, regardless of the intervention. Received: 1 October 1999 Final revision received: 6 January 2000 Accepted: 4 February 2000  相似文献   
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